Drum sieve machine

ABSTRACT

The invention refers to a trommel screen machine, comprising at least one revolving screening drum ( 2 ), at least one drive ( 3 ) for the screening drum, a feeding hopper ( 4 ) as well as at least one collecting device, respectively transport device ( 6 ), for collecting, respectively transporting the screened good.  
     The invention is characterised by the fact that in front of and/or on the trommel screen machine ( 1 ) at least one disc screen ( 5 ) is arranged which screens a defined grain, in particular oversized particles.

This is a nationalization of PCT/EP04/006840 filed Jun. 24, 2004 andpublished in German.

DESCRIPTION

The invention refers to a trommel screen machine with at least onerevolving screening drum, one feeding hopper, one drive, and at leastone collecting device, respectively transport device, for transportingthe screened good.

Trommel screen machined are known. They are used, for example, inrecycling and sorting plants for separating material of different size,respectively graining. They offer altogether a wide range ofapplication, for example for screening and classification of compost, inthe recycling of tailings, for waste dump regeneration, screening ofbark cuttings, shredded material, matured timber cuttings, treecuttings, mixed construction waste, rumble, cinder, gravel, soils or thelike.

With the trommel screen machines known so far it has to be seen as adisadvantage that as screened good only the good which is determined bythe size of the openings in the screening drum has a defined particlesize. The screened good which is conveyed out of the screening drum atits end in the direction of transport of the screening good, contains,as a rule, large amounts of oversized particles, so that this good hasto be screened one more time, or has to be put altogether again in acomminution machine in order to get it in a certain, determinedgraining.

Thus the material finally leaving the screening drum has a particle sizewhich can be assigned to a certain, determined size at about 90 percent.However, about 10 percent are obtained as oversized particles so that itis necessary to screen again or to put the complete good of thisfraction to a comminution machine. This problem also occurs if a stonegrit at the feeding hopper prevents certain oversized particles fromentering. Here higher amounts of working time and energy occur which canalso lead to the fact that the known trommel screen machines are onlyapplied for pre-sorting, or are only used for screening good where thepercentage of deviations from the graining described above can beneglected because they are too small.

This problem occurs in particular, for example, with trees fromclearings, matured timber, cross-sills or the like comminuted, forexample, by means of drum disintegrators or shredders. But also in theprocessing of tailings this problem is relevant.

Coming from the state of the art known as above it is an object of theinvention to provide a trommel screen machine which does no more havethe disadvantages described above.

The problem of the invention is solved by a trommel screen machine,comprising at least one revolving screening drum, at least one drive forthe screening drum, a feeding hopper as well as at least one collectingdevice, respectively transport device, for collecting, respectivelytransport, of the screened good, which is characterised by the fact thatin front of and/or on the trommel screen machine at least one discscreen is arranged which screens defined grain, in particular oversizedparticles. By means of the arrangement of a disc screen in front of,respectively on, the trommel screen machine the good leaving the screendrum at its end is determined as screened good of a defined graining.The width of the passage of the disc screen now defines sufficientlyaccurately the maximum graining of the mixing good.

In a trommel screen machine automatically another screened fraction isobtained which can be seen as defined, which leaves the drum screen atits end. The passage of the oversized particles through the disc screenis not possible anymore as it is the case, for example, with known stonegrits. Therefore the invention provides a trommel screen machine whichmakes an additional defined fractioning of mixed good possible. It isnot relevant here whether so far one, two or three defined fractionshave been provided by the respective trommel screen machine. In eachcase one defined fraction in addition to the fractions provided so faris obtained. The technical expenses concerning the plants, but also theprocess is reduced, energy is saved. This advantage occurs in particularby means of the arrangement of the disc screen directly before or on thetrommel screen machine.

A development of the trommel screen machine according to the inventionis therefore characterised by the fact that the disc screen is arrangedon the feeding hopper of the trommel screen machine. Here the advantageof the invention as described before becomes particularly clear. Bymeans of a simple, however effective, technical measurement a trommelscreen machine with considerably improved features of use is obtained.

Another aspect of the invention concerns a trommel screen machine asdescribed above which is characterised by the fact that the disc screenis designed in such a way that it can be folded, respectively turned,away. By means of this maintenance and cleaning are made considerablyeasier. For example, obstructions during the recycling of tailings canbe removed very easily after turning away the disc screen.

According to the invention it has also been found to be an advantage ifthe trommel screen machine is characterised by a common drive for thescreening drum and the disc screen. The technical expenses for machines,respectively plants, are thus reduced further. The drive for a screeningdrum is mostly dimensioned in such a way that a disc screen can actuallyalso be driven by means of the drive of the screening drum. In the casethat the drive is, for once, not dimensioned sufficiently so that it candrive both components the use of a larger dimensioned drive is mostlymore convenient than the use of two separate drives.

Furthermore it is an advantage if at least the drive for the screeningdrum of the trommel screen machine is designed as direct drive,preferably as direct drive by means of a pinion. Thus the expenses for agear are saved. The speed control in modern drives can be easilycontrolled by this drive.

A development of the trommel screen machine according to the inventionis characterised by the fact that the dimensions of the disc screen areadapted to the size of the feeding hopper. Thus partial adaptations,respectively covers, in the feeding region are not necessary anymore.

According to another embodiment of the invention it is provided that thedisc screen is arranged on the feeding hopper at an angle (alpha)inclined seen in the direction of transport of the screening drum. Thismakes screening, respectively sieving, of the oversized particles and,in particular, its transport easier. In the same it is achieved by thatthat all grainings of the screening good defined by the screen reachthen the screening drum through the disc screen.

It has been found, according to a development of the trommel screenmachine of the invention, to be an advantage if at least one adjustingdevice is provided by means of which the angle (alpha) of the discscreen can be adjusted with regard to the feeding hopper. Thus the anglecan be varied easily according to the screening good so that the trommelscreen machine can be used even more universally.

The trommel screen machine according to the invention is alsocharacterised by the fact that a conveying device, for example aconveyor belt or a chute is provided for transporting the definedoversized particles. Thus the transport is made considerably moreeasier. For example, the oversized particles can be conveyed by theconveyor belt or chute, if necessary, via another conveyor belt one moretime in a comminution machine, before it is then again, but once morecomminuted, conveyed in the trommel screen machine.

Furthermore it is an advantage here if the conveying device is designedmultipart, in particular in such a way that it can be angled,respectively turned away. In particular with mobile installations thisis a measurement which makes transporting the machine easier.

Another advantage of the trommel screen machine according to theinvention is given, according to a development, by the fact that theconveying direction of the conveying device for the oversized particleswhich have to be transported away is opposed to conveying direction ofthe screened good. Fractioning of the mixed good is thus influenced in apositive way.

According to the invention it has also been found to be an advantage ifthe conveying device is arranged before the feeding hopper with regardto the conveying direction of the screening good. The advantagesreferring the transport of a machine of this kind occur in the same wayas described above.

According to a development of the trommel screen machine, as describedbefore, it is provided that the disc screen is designed in such a waythat it can be changed, respectively removed, in such a way that atleast one stone grit, vibrating screen or the like can be arrangedinstead of the disc screen. This has the advantage that the machine banbe used in the known way, if, according to the nature of the screeninggood the use of a disc screen is not necessary.

Here it is provided, according to another aspect of the solution, thatthe stone grit, respectively the vibrating screen, is also designed thatit can be folded, respectively turned away. This also results in aneasier maintenance, respectively removal of troubles.

The problem of the invention is also solved by a disc screen, inparticular for a trommel screen machine as described above, comprisingat least two driven shafts provided with discs, the discs being arrangedon the different shafts staggered, respectively engaging comb-like, toeach other which is characterised by the fact that the shafts aredesigned in such a way that they can be exchanged. The possibility ofexchanging the shafts makes the use of different shafts on, respectivelyin, a disc screen possible. Thus it is also a fact that differentdiameters of shafts, different diameters of discs, different distanceson the shaft are possible on a single basic body of a disc screen. Wornshafts can be exchanged easily. Also resetting for different objectionsis now possible easily. By supplying differently equipped shafts auniversal use is possible.

A convenient development of the disc screen described before thereforeprovide that the number, size and the distance of the discs to oneanother on the shafts can be varied.

Another aspect of the invention refers to a disc screen which ischaracterised by the fact that at least one of the discs is a polygondiffering from the circle-shape.

It is furthermore provided that the discs are designed, according to adevelopment of the disc screen described before, in such a way that theycan be exchanged, in particular be pinned up, respectively inserted.Thus worn discs can be exchanged very conveniently. Also discs ofdifferent shapes and sizes may be positioned on one shaft.

Another modification of the disc screen according to the invention asdescribed above, is characterised by the fact that spacers are providedwhich can be pinned, respectively inserted, on the shaft between thediscs, and which are held by means of a clamping device on the shaft.Thus an exchange is even more efficient.

It is furthermore an advantage to provide at least one of the discs withat least one nap. The arrangement of naps leads to a further improvementof the screening result. In particular long pieces are prevented frompassing through the screen, the dimensions of which are for example suchthat they might pass the screen on edge. Thus observing of the oncepre-determined particle size is even more secured altogether.

Conveniently the nap is here attached to the perimeter of the discs.

It has been found here to be an advantage, if the discs have, arrangedat the perimeter, several borings in each of which a nap can be fixed,respectively attached to, in a releasable, fixed way.

According to the concept of the invention to guarantee a high number ofdifferent applications of the trommel screen machine, it is providedfurthermore that the number, size and shape of the naps is designed suchthat it can be varied, in particular be changed, respectively beexchanged.

The naps have, for example, a rectangular, square, circular,respectively oval, cross section. The shape of the naps, as mentionedbefore, must not be understood here as restricting in any way. Thatdepends on the respective screening application.

The invention also refers to a trommel screen machine with a disc screenas described before.

The invention also provides a recycling plant, respectively a sortingplant, with at least one trommel screen machine as described above,and/or at least one disc screen, as described above.

In the following the invention is described further by means ofembodiments and drawings.

In the drawings:

FIG. 1 section through a trommel screen machine according to theinvention

FIGS. 2 a and 2 b embodiment of a disc screen according to the invention

FIGS. 3 a and 3 b side and front view of an embodiment of a shaft

FIGS. 4 a and 4 b embodiment of a nap

FIG. 1 is a section through an embodiment of a trommel screen machineaccording to the invention. Reference number 1 here indicates thetrommel screen machine altogether. On the left hand side of the drawingthe screening drum 2 is arranged. The arrow with reference number Awithin the screening drum 2 refers to the conveying direction of thescreening good within the screening drum. At the end of the screeningdrum 2 there is a first collecting and transport device 6/1 underneathfor the screened, respectively sieved, good which gets through theopenings of the screening drum 2 in a collecting room not shown indetail. Via a conveyor belt as part of the collecting and transportingdevice 6/1 the screened good is conveyed away from the trommel screenmachine.

At the end of the screening drum 2 another collecting and transportdevice 6/2 is arranged. During screening it is lowered, respectivelyfolded down, so that the good moved back within the screening drum 2 canleave there, and can be also transported away by means of the device,for example a conveyor belt. The screened good which is conveyed out ofthe screening drum in the transport direction A of the screening good atthe end of the screening drum 2, still has, according to the state ofthe art, in the average large amounts of oversized particles, so thatthis good has to be screened once more or it has to be put again in acomminution machine altogether in order to get a determined particlesize.

This problem is removed according to the invention by the arrangement ofan additional disc screen 5 on, respectively in front of, the trommelscreen machine 1. In the shown embodiment the disc screen 5 is arrangedon the feeding hopper 4. The disc screen 5 is here arranged on thefeeding hopper 4 at an inclined angle alpha with regard to the transportdirection. Angle alpha can be designed, respectively adjusted, hereaccording to the respective screening task.

The screening good is, according to the invention, passed at first overthe disc screen 5, from which the graining defined by the adjustment ofthe disc screen 5 gets in the feeding hopper 4 and then in the screeningdrum 2. The screening drum 2 has openings which may be defined, forexample, according to the undersized particles for the screening good.These undersized particles then are collected by the collecting andtransport device 6/1 and transported away. The good now determined bythe adjustment of the disc screen 5 and the size of the openings of thescreening drum 2 now reaches the end of the screening drum 2 and thenleaves it to the collecting and transport device 6/2.

The oversized particles which do not get through the screening drum areconveyed by the disc screen 5 to a conveying device 6/3 which conveys ina conveying direction B opposed to the conveying direction A of thescreening good in the screening drum 2. The conveying device 6/3 isshown in the drawing according to FIG. 1 in a folded position for thetransport of the trommel screen machine 1.

Thus the result of a trommel screen machine 1 according to theembodiment described before are two defined fractions of the mixed goodfor immediate use, respectively processing, and the oversized particleswhich have to be transported again, if necessary, to a comminutionmachine. Reference number 3 indicates the drive which is used fordriving screening drum 2 as well as disc screen 5.

FIGS. 2 a and 2 b show an embodiment of a disc screen 5 according to theinvention. Here several shafts 7 are arranged one behind the other inthe conveying direction C. The second shaft 7 located in the conveyingdirection C is squared the square being connected with the drive, forexample, via a gear. The single shafts 7 are coupled to one another sothat the drive can be carried out via a single shaft 7. On the shafts 7the discs 8 are arranged. These may be arranged fixedly, for examplewelded, as well as releasably fixedly on the shaft 7, for example bymeans of a clamping device. The size of the discs 8, their number andthe distance between them can be varied according to the respectivescreening task. For that reason it is also an advantage if the shafts 7are designed in such a way that they can be changed, respectivelyexchanged. The discs 8 are here attached to the different shafts 7 insuch away that the discs 8 are arranged staggered, respectively engagingcomb-like to one another. The distance of the discs 8 to one another,respectively the occurring spaces between the discs, define the size ofthe particles, respectively the largest dimension of the screeningmaterial.

FIG. 3 a shows a side view through an embodiment of a shaft 7 for a discscreen 5. Reference number 7 indicates the shaft. On the shaft 7 spacers11 and discs 8 are arranged alternating. The shaft 7 is attached to,respectively on, the basic frame, respectively basic body (not shown inthe figure) of the disc screen 5 by means of a bearing box 13. Thebearing box has openings which are provided for attaching the shaft, forexample, by means of screws to the basic frame, respectively basic body.A clamping device, which is not shown in detail, keeps the discs 8 andthe spacers 11 on the shaft 7.

In FIG. 3 b the front view of the view according to FIG. 3 a is shown.Here borings are indicated which serve for holding, respectively fixing,naps 9. The borings 10 are arranged here on the perimeter of the disc 8.

In FIGS. 4 a and 4 b an embodiment of a nap 9 is presented. In the nap 9here a recess 12, respectively an impression, is provided in which anot-shown fastening means may be located. Reference number 15 indicatesthe boring through which the not-shown fastening means is guided if thenap 9 is connected through the boring 10 with the disc 8.

Before the invention has been described by way of examples. The claimsfiled now and to be filed later on together with the application areattempted formulations without prejudice for obtaining a broaderprotection.

References in the sub-claims relate to the further design of the matterof the main claim through the characteristics of the respectivesub-claim. These are, however, not to be understood as a waiver ofindependent protection of the matter for the characteristics of thereferred sub-claims.

Characteristics only disclosed in the description so far may, in thecourse of proceedings, be claimed as being of inventive relevance, forexample to distinguish from the state of the art.

1-25. (canceled)
 26. Trommel screen machine, comprising at least onerevolving screening drum, at least one drive for the screening drum, afeeding hopper, at least one disc screen, as well as at least onecollecting device, respectively transport device, for collecting,respectively transporting, the screened good, characterised in that thedisc screen is arranged on the trommel screen machine, and the discscreen screens defined grain, in particular oversize particles.
 27. Thetrommel screen machine according to claim 26, characterised in that thedisc screen is arranged on the feeding hopper of the trommel screenmachine.
 28. The trommel screen machine according to claim 26,characterised in that the disc screen is designed in such a way that itcan be folded, respectively turned, away.
 29. The trommel screen machineaccording to claim 26, characterised by a common drive for the screeningdrum and the disc screen.
 30. The trommel screen machine according toclaim 26, characterised in that at least the drive for the screeningdrum is designed as direct drive, preferably by means of a pinion. 31.The trommel screen machine according to claim 26, characterised in thatthe dimensions of the disc screen is adapted to the size of the feedinghopper.
 32. The trommel screen machine according to claim 26,characterised in that the disc screen is arranged at an angle (alpha)which is inclined seen in transport direction (A) of the screening goodin the screening drum on the feeding hopper.
 33. The trommel screenmachine according to claim 26, characterised in that at least oneadjusting device is provided by means of which the angle (alpha) of thedisc screen can be adjusted with regard to the feeding hopper.
 34. Thetrommel screen machine according to claim 26, characterised in that aconveying device, for example a conveyor belt or a chute, is providedfor transporting the defined oversized particles.
 35. The trommel screenmachine according to claim 26, characterised in that the conveyingdevice has a multipart design, in particular in such a way that it canbe angled or turned away.
 36. The trommel screen machine according toclaim 26, characterised in that the conveying direction (B) of theconveying device for the transported oversized particles is opposed tothe transport direction (A) of the screening good.
 37. The trommelscreen machine according to claim 26, characterised in that theconveying device is arranged before the feeding hopper with regard tothe transport direction (A) of the screening good.
 38. The trommelscreen machine according to claim 26, characterised in that the discscreen is designed in such a way that it can be exchanged, respectivelyremoved, such that at least, for example, one vibrating screen can bearranged instead of the disc screen.
 39. The trommel screen machineaccording to claim 26, characterised in that the disc screen is designedin such a way that it can be exchanged, respectively removed, such thatat least, for example, one vibrating screen can be arranged instead ofthe disc screen and the vibrating screen is designed in such a way thatit can also be folded, respectively turned away.
 40. The trommel screenmachine according to claim 26, characterised in that a disc screen isprovided, comprising at least two driven shafts provided with discs, thediscs being arranged on the different shafts staggered to each other,respectively comb-like engaging, and the shafts are designed in anexchangeable way.
 41. The trommel screen machine according to claim 26,characterised in that a disc screen is provided, comprising at least twodriven shafts provided with discs, the discs being arranged on thedifferent shafts staggered to each other, respectively comb-likeengaging, and the shafts are designed in an exchangeable way and thenumber, size and distance of the discs to one another can be varied onthe shafts.
 42. The trommel screen machine according claim 26,characterised in that a disc screen is provided, comprising at least twodriven shafts provided with discs, the discs being arranged on thedifferent shafts staggered to each other, respectively comb-likeengaging and at least one of the discs differs from the circular shapeand is designed as a polygon.
 43. The trommel screen machine accordingto claim 26, characterised in that a disc screen is provided, comprisingat least two driven shafts provided with discs, the discs being arrangedon the different shafts staggered to each other, respectively comb-likeengaging, and the discs are designed in such a way that they can beexchanged, in particular be pinned up, respectively inserted, on theshaft.
 44. The trommel screen machine according to claim 26,characterised in that a disc screen is provided, comprising at least twodriven shafts provided with discs, the discs being arranged on thedifferent shafts staggered to each other, respectively comb-likeengaging, spacers are provided which can be pinned up, respectivelyinserted, between the discs on the shaft, and which are held on theshaft by means of a clamping device.
 45. The trommel screen machineaccording to claim 26, characterised in that a disc screen is provided,comprising at least two driven shafts provided with discs, the discsbeing arranged on the different shafts staggered to each other,respectively comb-like engaging and at least one of the discs has atleast one nap.
 46. The trammel screen machine according to claim 26,characterised in that a disc screen is provided, comprising at least twodriven shafts provided with discs, the discs being arranged on thedifferent shafts staggered to each other, respectively comb-likeengaging and at least one of the discs has at least one nap and the napis attached to the perimeter of the discs.
 47. The trommel screenmachine according to claim 26, characterised in that a disc screen isprovided, comprising at least two driven shafts provided with discs, thediscs being arranged on the different shafts staggered to each other,respectively comb-like engaging and at least one of the discs has atleast one nap and the discs have, arranged on the perimeter, severalborings in each of which at least one nap can be fixed in a releasableway.
 48. The trommel screen machine according to claim 26, characterisedin that a disc screen is provided, comprising at least two driven shaftsprovided with discs, the discs being arranged on the different shaftsstaggered to each other, respectively comb-like engaging and at leastone of the discs has at least one nap and the number, size and shape ofthe naps can vary, in particular that they are designed to bechangeable, respectively exchangeable.
 49. The trommel screen machineaccording to claim 26, characterised in that a disc screen is provided,comprising at least two driven shafts provided with discs, the discsbeing arranged on the different shafts staggered to each other,respectively comb-like engaging and at least one of the discs has atleast one nap and naps have a rectangular, square, circular,respectively oval, cross section.
 50. The recycling plant, respectivelysorting plant, with at least one trommel screen machine according toclaim
 26. 51. The recycling plant according to claim 26, characterisedin that a disc screen is provided, comprising at least two driven shaftsprovided with discs, the discs being arranged on the different shaftsstaggered to each other, respectively comb-like engaging, and the shaftsare designed in an exchangeable way.